KR102547468B1 - Organic Electroluminescent Device Comprising an Electron Buffer Layer and an Electron Transport Layer - Google Patents

Abstract

The present invention relates to an organic electroluminescent device. The organic electroluminescent device of the present invention can exhibit high efficiency and/or long lifespan by including a specific combination of an electron buffer material and an electron transport material.

Description

Organic electroluminescent device comprising an electron buffer layer and an electron transport layer {Organic Electroluminescent Device Comprising an Electron Buffer Layer and an Electron Transport Layer}

The present invention relates to an organic electroluminescent device comprising an electron buffer layer and an electron transport layer.

An electroluminescent device (EL device) is a self-luminous display device and has advantages of a wide viewing angle, excellent contrast, and fast response speed. In 1987, Eastman Kodak Co., Ltd. first developed an organic electroluminescent device using a low-molecular aromatic diamine and an aluminum complex as a material for forming a light emitting layer [see Appl. Phys. Lett. 51, 913, 1987].

An organic electroluminescent device (OLED) is a device that converts electrical energy into light by applying electricity to an organic light emitting material, and has a structure that usually includes an anode (anode) and a cathode (cathode) and an organic material layer therebetween. The organic material layer of the organic electroluminescent device may include a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer (including a host and a dopant material), an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like. The materials used for are divided into hole injection materials, hole transport materials, electron blocking materials, light emitting materials, electron buffer materials, hole blocking materials, electron transport materials, and electron injection materials according to their functions. In such an organic electroluminescent device, holes are injected from the anode and electrons from the cathode are injected into the light emitting layer by application of a voltage, and excitons with high energy are formed by recombination of the holes and electrons. The organic light emitting compound is brought into an excited state by this energy, and as the excited state of the organic light emitting compound returns to a ground state, energy is emitted as light to emit light.

In the organic electroluminescent device, the electron transport material serves to smoothly transfer electrons from the cathode to the light emitting layer and increases the chance of recombination of holes and electrons in the light emitting layer by suppressing the movement of holes that are not combined in the light emitting layer, and has excellent electron affinity. material is used Conventionally, organometallic complexes having a light emitting function such as Alq ₃ have excellent electron transfer ability and have been used as electron transfer materials. However, there was a problem that Alq ₃ moved to another layer, and color purity was reduced when used in a blue light emitting device. Therefore, there is a need for a new electron transport material capable of exhibiting high luminous efficiency in a light emitting device by showing fast electron transfer characteristics when used in an organic electroluminescent device having high electron affinity without the above problems.

In addition, the electronic buffer layer is a layer that can improve the problem that the current characteristics in the device change when exposed to high temperatures in the panel manufacturing process, which can cause a problem of deformation of light emission luminance. In order to secure the stability according to the above, the characteristics of the compound included in the electron buffer layer are important.

In addition, the fluorescent light emitting material has lower efficiency characteristics than the phosphorescent light emitting material in terms of material. Accordingly, an attempt was made to improve the efficiency through a specific fluorescent light emitting material such as a combination of an anthracene-based host and a pyrene-based dopant, but these have large hole traps, and the light emitting region in the light emitting layer tends to be biased towards the hole transport layer, resulting in interfacial light emission. , such interfacial light emission not only has a problem of reducing device lifetime, but also has unsatisfactory efficiency. Accordingly, as one of the methods for improving the problems of the fluorescent light emitting material, an attempt is being made to solve the efficiency and lifespan simultaneously by inserting an electron buffer layer between the light emitting layer and the electron transport layer.

Korean Patent Publication No. 2015-0080213 discloses an organic electroluminescent device including an electron transport layer having a two-layer structure including an anthracene-based compound and a heteroaryl-based compound.

Korean Patent Publication No. 2015-0108330 discloses an organic electroluminescent device including a compound in which nitrogen-containing heteroaryl is bonded to carbazole or the like as an electron buffer material.

Korean Patent Publication No. 2015-0024491 and Korean Patent Publication No. 2015-0099750 disclose an electron buffer layer or an electron transport layer including a compound containing an azine ring.

However, the above documents do not specifically disclose an organic electroluminescent device including a compound containing nitrogen-containing heteroaryl as an electron buffer material and a compound in which 5-membered heteroaryl is fused to phenanthrene as an electron transport material.

Korean Patent Publication No. 2015-0080213 (published on July 9, 2015) Korean Patent Publication No. 2015-0108330 (published on September 25, 2015) Korean Patent Publication No. 2015-0024491 (published on March 9, 2015) Korean Patent Publication No. 2015-0099750 (published on September 1, 2015)

An object of the present invention is to provide an organic electroluminescent device having high efficiency and/or long lifespan by including a specific combination of an electron buffer material and an electron transport material.

As a result of intensive research to solve the above technical problem, the present inventors have found a first electrode; a second electrode facing the first electrode; a light emitting layer between the first electrode and the second electrode; and an electron transport layer and an electron buffer layer between the light emitting layer and the second electrode, wherein the electron buffer layer includes a compound represented by Formula 1 below, and the electron transport layer includes a compound represented by Formula 2 below. The present invention was completed by finding that an organic electroluminescent device achieves the above object.

[Formula 1]

[Formula 2]

In Formulas 1 and 2,

N ₁ and N ₂ are each independently N or CR ₁₁ provided that at least one of N ₁ and N ₂ is N;

X ₁ to X ₃ are each independently N or CR ₁₂ ;

Y ₁ is N or CR ₁₃ ;

R ₁₁ to R ₁₃ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C50)aryl, substituted or unsubstituted (3- 50 member) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tri(C1-C30) alkylsilyl, substituted or unsubstituted Di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri(C6-C30)arylsilyl, substituted Or unsubstituted mono- or di- (C1-C30) alkylamino, substituted or unsubstituted mono- or di- (C6-C30) arylamino, or substituted or unsubstituted (C1-C30) alkyl (C6- C30) arylamino; It may be linked to an adjacent substituent to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic or combination thereof ring, and the carbon of the formed alicyclic, aromatic or combination thereof ring atoms may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur;

A ₁ is -N=, -NR ₇ -, -O- or -S-;

B ₁ is -N=, -NR ₈ -, -O-, or -S-, wherein, when A ₁ is -N=, B ₁ is -NR ₈ -, -O-, or -S-, and A ₁ is - B ₁ when NR ₇ - is -N=, -O- or -S-;

R ₁ is a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (3-30 membered) heteroaryl;

R ₂ to R ₄ , R ₇ and R ₈ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted Unsubstituted (3-30 membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tri(C1-C30) alkylsilyl , substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri(C6- C30) arylsilyl, substituted or unsubstituted mono- or di- (C1-C30) alkylamino, substituted or unsubstituted mono- or di- (C6-C30) arylamino, or substituted or unsubstituted (C1- It may be C30)alkyl(C6-C30)arylamino, or may be linked to an adjacent substituent to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic, or a combination thereof ring. A carbon atom of an alicyclic, aromatic or combination ring may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur;

a is 1, b and c are each independently 1 or 2, d is an integer from 1 to 4;

The heteroaryl (ene) includes one or more heteroatoms selected from B, N, O, S, Si and P.

According to the present invention, an organic electroluminescent device having high efficiency and/or long lifespan is provided, and a display device or lighting device using the same can be manufactured.

1 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.
2 schematically illustrates the relationship of energy gaps between layers of an organic electroluminescent device according to an embodiment of the present invention.
3 is a graph showing current efficiency according to luminance of organic electroluminescent devices of Comparative Example 1 and Device Example 2.

Although the present invention is described in more detail below, it is for illustrative purposes only and should not be construed in any way to limit the scope of the present invention.

As used herein, "organic electroluminescent compound" refers to a compound that can be used in an organic electroluminescent device, and may be included in an arbitrary layer constituting an organic electroluminescent device, if necessary.

As used herein, “organic electroluminescent material” refers to a material that can be used in an organic electroluminescent device, and may include one or more compounds, and may be included in an arbitrary layer constituting an organic electroluminescent device, if necessary. For example, the organic electroluminescent material may be a hole injection material, a hole transport material, a hole auxiliary material, a light emitting auxiliary material, an electron blocking material, a light emitting material, an electron buffer material, a hole blocking material, an electron transport material, or an electron injection material. can

In an organic electroluminescent device including first and second electrodes and a light emitting layer, an electron buffer layer is inserted between the light emitting layer and the second electrode to secure efficiency and / or lifetime correlation according to electron injection control by the LUMO energy value of the electron buffer layer you can focus on

Originally, the lowest unoccupied molecular orbital (LUMO) energy and the highest occupied molecular orbital (HOMO) energy have negative values, but in the present invention, the LUMO energy value (A) and the HOMO energy value are expressed as absolute values for convenience. Also, when comparing the magnitudes of LUMO energy values, the absolute values are compared as a standard. The LUMO energy value and the HOMO energy value in the present invention are based on values calculated by Density Functional Theory (DFT).

The LUMO energy value can be easily measured by various known methods. Typically, LUMO energy values are measured using cyclic voltammetry or ultraviolet photoelectron spectroscopy (UPS). Therefore, those skilled in the art can implement the present invention by easily identifying the electron buffer layer, the light emitting layer, and the electron transport layer that satisfy the LUMO energy value relationship of the present invention. The HOMO energy value can also be easily measured in the same way as the LUMO energy value.

The present invention is a first electrode; a second electrode facing the first electrode; a light emitting layer between the first electrode and the second electrode; and an electron transport layer and an electron buffer layer between the light emitting layer and the second electrode, wherein the electron buffer layer includes a compound represented by Formula 1, and the electron transport layer includes a compound represented by Formula 2. It relates to a light emitting device.

An electron buffer layer and an electron transport layer are inserted between the light emitting layer and the second electrode. The electron buffer layer may be provided between the light emitting layer and the electron transport layer, or between the electron transport layer and the second electrode.

An electron buffer material included in the electron buffer layer refers to a material that controls charge flow characteristics. Accordingly, the electron buffer material may trap electrons, block electrons, or lower an energy barrier between the electron transport band and the light emitting layer. In an organic electroluminescent device, the electron buffering material may be used for an electron buffering layer or may be incorporated into another region such as an electron transporting region or an emission layer. Here, the electron buffer layer is formed between the light emitting layer of the organic electroluminescent device and the electron transfer band, or formed between the electron transfer band and the second electrode. The electron buffer material may further include a conventional material used in the manufacture of an organic electroluminescent device in addition to the compound of Formula 1.

The electron transport material included in the electron transport layer serves to smoothly transfer electrons from the cathode to the light emitting layer and increases the chance of recombination of holes and electrons in the light emitting layer by suppressing the movement of holes that are not combined in the light emitting layer. This excellent material is used. Here, the electron transport layer is formed in an electron transport band between the second electrode of the organic electroluminescent device and the light emitting layer. In addition to the compound of Formula 2, the electron transport material may further include a conventional material used in the manufacture of an organic electroluminescent device.

"(C1-C30)alkyl" as described in the present invention means straight-chain or branched-chain alkyl having 1 to 30 carbon atoms constituting the chain, preferably 1 to 10 carbon atoms, and 1 to 6 carbon atoms it is more preferable Specific examples of the alkyl include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. As used herein, "(C2-C30)alkenyl" means a straight or branched chain alkenyl having 2 to 30 carbon atoms constituting the chain, preferably 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms. desirable. Specific examples of the alkenyl include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 2-methylbut-2-enyl, and the like. As used herein, "(C2-C30)alkynyl" means straight or branched chain alkynyl having 2 to 30 carbon atoms constituting the chain, preferably 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms. desirable. Examples of the alkynyl include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, and 1-methylpent-2-ynyl. As used herein, “(C3-C30)cycloalkyl” means a monocyclic or polycyclic hydrocarbon having 3 to 30 carbon atoms in the ring skeleton, preferably 3 to 20 carbon atoms, and more preferably 3 to 7 carbon atoms. Examples of the cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like. As used herein, "(3-7 membered) heterocycloalkyl" has 3 to 7 ring skeleton atoms, and at least one heteroatom selected from the group consisting of B, N, O, S, Si and P, preferably O, S And cycloalkyl containing one or more heteroatoms selected from N, and examples thereof include tetrahydrofuran, pyrrolidine, thiolane, and tetrahydropyran. As used herein, "(C6-C30)aryl(ene)" means a monocyclic or fused ring radical derived from an aromatic hydrocarbon having 6 to 30 ring skeleton carbon atoms, which may be partially saturated, where the ring skeleton carbon atoms are It is preferably 6 to 20, and more preferably 6 to 15. Examples of the aryl include phenyl, biphenyl, terphenyl, naphthyl, binapthyl, phenylnaphthyl, naphthylphenyl, fluorenyl, phenylfluorenyl, benzofluorenyl, dibenzofluorenyl, and phenane. trenyl, phenylphenanthrenyl, anthracenyl, indenyl, triphenylenyl, pyrenyl, tetracenyl, perylenyl, chrysenyl, naphthacenyl, fluoranthenyl, and the like. As used herein, “(3-30 membered) heteroaryl (ene)” refers to an aryl group having 3 to 30 ring skeleton atoms and containing at least one heteroatom selected from the group consisting of B, N, O, S, Si and P. it means. Here, the number of ring skeleton atoms is preferably 3 to 20, more preferably 5 to 15. The number of hetero atoms is preferably 1 to 4, and may be a single ring system or a fused ring system condensed with one or more benzene rings, and may be partially saturated. In addition, the heteroaryl (ene) herein includes a form in which one or more heteroaryl or aryl groups are connected to a heteroaryl group by a single bond. Examples of the heteroaryl include furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, thiadiazolyl, isothiazolyl, isoxazolyl, oxazolyl, oxadiazolyl, triazinyl, tetrazinyl , triazolyl, tetrazolyl, furazanyl, pyridyl, pyrazinyl, pyrimidinyl, single ring heteroaryl such as pyridazinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, dibenzofuranyl, di Benzothiophenyl, Benzonaphthothiophenyl, Benzoimidazolyl, Benzothiazolyl, Benzoisothiazolyl, Benzoisoxazolyl, Benzoxazolyl, Isoindolyl, Indolyl, Indazolyl, Benzothiadiazolyl, Quinolyl , isoquinolyl, cinnolinyl, quinazolinyl, quinoxalinyl, carbazolyl, phenoxazinyl, phenanthridinyl, fused ring system heteroaryl such as benzodioxolyl, and the like. As used herein, “halogen” includes F, Cl, Br and I atoms.

In addition, 'substitution' in the description of "substituted or unsubstituted" described in the present invention means that a hydrogen atom in a functional group is replaced with another atom or another functional group (ie, a substituent). Substituted alkyl, substituted aryl, substituted heteroaryl, substituted cycloalkyl, substituted alkoxy, substituted in R ₁ to R ₄ , R ₇ , R ₈ , and R ₁₁ to R ₁₃ of Formulas 1 and 2 above trialkylsilyl, substituted dialkylarylsilyl, substituted alkyldiarylsilyl, substituted triarylsilyl, substituted mono- or di-alkylamino, substituted mono- or di-arylamino, substituted alkylarylamino and Substituents of substituted monocyclic or polycyclic alicyclic, aromatic, or combinations thereof are each independently deuterium, halogen, cyano, carboxyl, nitro, hydroxy, (C1-C30)alkyl, halo (C1-C30 ) Alkyl, (C2-C30) alkenyl, (C2-C30) alkynyl, (C1-C30) alkoxy, (C1-C30) alkylthio, (C3-C30) cycloalkyl, (C3-C30) cycloalkenyl , (3-30 membered) heterocycloalkyl, (C6-C30) aryloxy, (C6-C30) arylthio, (C6-C30) aryl unsubstituted or substituted (3-30 membered) heteroaryl, (3 -30 member) heteroaryl substituted or unsubstituted (C6-C30) aryl, tri (C1-C30) alkylsilyl, tri (C6-C30) arylsilyl, di (C1-C30) alkyl (C6-C30) aryl Silyl, (C1-C30)alkyldi(C6-C30)arylsilyl, amino, mono- or di- (C1-C30)alkylamino, mono- or di- (C6-C30)arylamino, (C1-C30) Alkyl (C6-C30) arylamino, (C1-C30) alkylcarbonyl, (C1-C30) alkoxycarbonyl, (C6-C30) arylcarbonyl, di (C6-C30) arylboronyl, di (C1 -C30)alkylboronyl, (C1-C30)alkyl(C6-C30)arylboronyl, (C6-C30)ar(C1-C30)alkyl and (C1-C30)alkyl(C6-C30)aryllo means one or more selected from the group consisting of

According to one embodiment of the present invention, the compound represented by Chemical Formula 1 included in the electron buffer layer may be represented by Chemical Formula 3 below.

[Formula 3]

In Formula 3,

Ar ₁ and Ar ₂ are as defined for R ₁₂ in Formula 1;

Y ₁ is as defined in Formula 1;

L is a single bond, substituted or unsubstituted (C6-C50) arylene, or substituted or unsubstituted (5-50 membered) heteroarylene;

Ar is a substituted or unsubstituted (C6-C50) aryl or a substituted or unsubstituted (5-50 membered) heteroaryl.

According to one embodiment of the present invention, the compound represented by Chemical Formula 3 included in the electron buffer layer may be represented by any one of Chemical Formulas 4 to 8 below.

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

In Formulas 4 to 8,

Ar ₁ , Ar ₂ , Y ₁ and L are as defined in Formula 3;

Ar ₃ to Ar ₉ and Ar ₁₃ to Ar ₁₉ each independently have the same definition as Ar ₁ in Chemical Formula 3;

X is CRaRb, NRc, O or S, wherein Ra, Rb and Rc are each independently the same as the definition of Ar ₁ in Formula 3;

K is CRd or N, where Rd is as defined for Ar ₁ in Formula 3;

M is O or S;

e, f, h, i and p are each independently an integer of 1 to 4, g and q are each independently an integer of 1 to 3, and n, o, r and s are each independently 1 or 2.

According to one embodiment of the present invention, the compound represented by Chemical Formula 4 included in the electron buffer layer may be represented by any one of Chemical Formulas 10 to 14 below.

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

In Formulas 10 to 14,

Ar ₁ , Ar ₂ , Y ₁ , L and X are as defined in Formula 4;

R ₂₁ to R ₃₅ are each independently as defined in Ar ₁ in Formula 4;

Z is the same as the definition of X in Formula 4;

L ₁ and L ₂ are each independently the same as the definition of L in Formula 4;

aa, dd, ee, gg, hh, jj, kk, and pp are each independently an integer from 1 to 4, bb, cc, ii, nn, and qq are each independently an integer from 1 to 3, and ff is 1 or 2.

According to one embodiment of the present invention, the compound represented by Chemical Formula 2 included in the electron transport layer may be represented by any one of Chemical Formulas 15 to 17 below.

[Formula 15]

[Formula 16]

[Formula 17]

In Formulas 15 to 17,

A ₁ , B ₁ , R ₁ to R ₄ , and a to c are as defined in Formula 2;

L ₃ is a single bond, substituted or unsubstituted (C6-C30)arylene, or substituted or unsubstituted (3-30 membered) heteroarylene;

X _a to X _c are each independently -N- or -CR ₉ -;

Ar ₂₁ and Ar ₂₂ are each independently a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (3-30 membered) heteroaryl;

R ₅ , R ₆ and R ₉ are the same as the definition of R ₂ in Formula 2;

U is a single bond or a substituted or unsubstituted (C1-C6)alkylene;

W is -NR-, -O-, -S- or -CR'R"-;

R is a substituted or unsubstituted (C6-C30) aryl or a substituted or unsubstituted (3-30 membered) heteroaryl;

R' and R" are each independently a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3-30 membered) heteroaryl;

d' and w are each independently an integer of 1 to 3, t and u are each independently an integer of 1 to 4, and v is 0 or 1.

In Formulas 1, 3 to 8, and 10 to 14, R ₁₁ to R ₁₃ , Ar ₁ to Ar ₉ , Ar ₁₃ to Ar ₁₉ , Ra to Rd, and R ₂₁ to R ₃₅ are each independently hydrogen, deuterium, Halogen, cyano, substituted or unsubstituted (C1-C30) alkyl, substituted or unsubstituted (C6-C50) aryl, substituted or unsubstituted (3-50 membered) heteroaryl, substituted or unsubstituted (C3 -C30)cycloalkyl, substituted or unsubstituted (C1-C30)alkoxy, substituted or unsubstituted tri(C1-C30)alkylsilyl, substituted or unsubstituted di(C1-C30)alkyl(C6-C30)aryl Silyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri(C6-C30)arylsilyl, substituted or unsubstituted mono- or di- (C1-C30 ) alkylamino, substituted or unsubstituted mono- or di- (C6-C30)arylamino, or substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino; It may be linked to an adjacent substituent to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic or combination thereof ring, and the carbon of the formed alicyclic, aromatic or combination thereof ring Atoms may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur. R ₁₁ to R ₁₃ , Ar ₁ to Ar ₉ , Ar ₁₃ to Ar ₁₉ , Ra to Rd, and R ₂₁ to R ₃₅ are each independently, preferably, hydrogen, substituted or unsubstituted (C6-C20) aryl , Or a substituted or unsubstituted (5-40 membered) heteroaryl; It may be connected with adjacent substituents to form a substituted or unsubstituted (C3-C15) monocyclic or polycyclic alicyclic or aromatic ring; More preferably, hydrogen; (C6-C20)aryl unsubstituted or substituted with (C1-C6)alkyl, (C6-C12)aryl or (5-15 membered)heteroaryl; or (5-40 membered) heteroaryl unsubstituted or substituted with (C1-C6)alkyl or (C6-C12)aryl; It may be connected with adjacent substituents to form a substituted or unsubstituted (C3-C15) monocyclic or polycyclic aromatic ring. R ₁₁ to R ₁₃ , Ar ₁ to Ar ₉ , Ar ₁₃ to Ar ₁₉ , Ra to Rd, and R ₂₁ to R ₃₅ are each independently hydrogen, phenyl, biphenyl, naphthyl, terphenyl, phenyl naphthyl, naphthylphenyl, anthracenyl, phenanthrenyl, dibenzofuranyl, dibenzothiophenyl or fluorenyl.

In Formulas 3 to 8 and 10 to 14, L is a single bond, substituted or unsubstituted (C6-C50) arylene, or substituted or unsubstituted (5-50 membered) heteroarylene. L is preferably a single bond, a substituted or unsubstituted (C6-C20)arylene, or a substituted or unsubstituted (5-40 membered)heteroarylene, more preferably a single bond, (C1- (C6-C20)arylene unsubstituted or substituted with C6)alkyl or (C6-C12)aryl, or (5-40 membered) unsubstituted or substituted with (C1-C6)alkyl or (C6-C12)aryl It is a heteroarylene. Specifically, L may be a single bond, phenylene, biphenylene, naphthylene, phenyl-naphthylene, naphthyl-phenylene, biphenyl-naphthylene or naphthyl-biphenylene.

In Formulas 2 and 15 to 17, R ₁ is a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (3-30 membered) heteroaryl, preferably a substituted or unsubstituted (C6-C30) -C30) aryl or substituted (5-25 membered) heteroaryl, more preferably substituted or unsubstituted (C6-C30) aryl or substituted (5-20 membered) heteroaryl, for example , unsubstituted phenyl, unsubstituted biphenyl, unsubstituted naphthyl, methyl-substituted fluorenyl, methyl-substituted benzofluorenyl, phenyl-substituted carbazolyl, phenyl-substituted benzocarbazolyl, phenyl substituted indolocarbazolyl, unsubstituted dibenzofuranyl, unsubstituted dibenzothiophenyl, spiro[fluorene-fluorene], or spiro[fluorene-benzofluorene].

In Formulas 2 and 15 to 17, R ₂ to R ₉ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, or substituted or unsubstituted (C6-C30)aryl , substituted or unsubstituted (3-30 membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tri(C1-C30) ) Alkylsilyl, substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri (C6-C30)Arylsilyl, substituted or unsubstituted mono- or di- (C1-C30)alkylamino, substituted or unsubstituted mono- or di- (C6-C30)arylamino, or substituted or unsubstituted (C1-C30) Alkyl (C6-C30) arylamino, or linked with adjacent substituents to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic, or a combination thereof ring, , Carbon atoms of the formed alicyclic, aromatic or combination thereof may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur, preferably each independently hydrogen, substituted or unsubstituted (C6- C25) aryl, substituted or unsubstituted (5-25 membered) heteroaryl, or substituted or unsubstituted mono- or di- (C6-C25) arylamino, or substituted or unsubstituted (C5 -C25) may form a monocyclic or polycyclic alicyclic or aromatic ring, and the carbon atoms of the formed alicyclic or aromatic ring may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur, more preferably are each independently hydrogen, substituted or unsubstituted (C6-C20) aryl, substituted or unsubstituted (5-25 membered) heteroaryl, or substituted or unsubstituted di(C6-C18) arylamino, or adjacent substituents It can be connected to form a substituted or unsubstituted (C5-C25) monocyclic or polycyclic alicyclic or aromatic ring, and the carbon atoms of the formed alicyclic or aromatic ring are composed of one or more heteroatoms selected from nitrogen and sulfur. can be replaced For example, R ₂ to R ₄ are each independently selected from hydrogen, substituted phenyl, substituted triazinyl, substituted pyrimidinyl, substituted or unsubstituted carbazolyl, substituted benzocarbazolyl, and unsubstituted dibenzocarba. It is selected from the group consisting of zolyl, and substituted or unsubstituted diphenylamino, or may be linked to an adjacent substituent to form a substituted indene ring or a substituted benzothiophene ring, R ₅ and R ₆ are each independently, A benzene ring selected from the group consisting of hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted carbazolyl, unsubstituted benzocarbazolyl, and unsubstituted dibenzocarbazolyl, or linked to an adjacent substituent to be unsubstituted; A phenyl substituted indole ring, a phenyl substituted benzoindole ring, a methyl substituted indene ring, or a methyl substituted benzoindene ring may be formed.

In Formulas 2 and 15 to 17, A ₁ is -N=, -NR ₇ -, -O- or -S-; B ₁ is -N=, -NR ₈ -, -O- or -S-; When A ₁ is -N=, B ₁ is -NR ₈ -, -O-, or -S-, and when A ₁ is -NR ₇ -, B ₁ is -N=, -O-, or -S- am. Here, R ₇ and R ₈ may be unsubstituted phenyl.

In Formulas 15 to 17, L ₃ is a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3-30 membered) heteroarylene, preferably a single bond, or It is a substituted or unsubstituted (C6-C18) arylene, more preferably a single bond or unsubstituted (C6-C12) arylene, and for example, it may be a single bond or unsubstituted phenylene.

In Formula 15, X _a to X _c are each independently -N- or -CR ₉ -, preferably X _a to X _c At least one of is -N-, more preferably at least two of X _a to X _c are -N-. Here, R ₉ may be hydrogen.

In Formula 15, Ar ₂₁ and Ar ₂₂ are each independently a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (3-30 membered) heteroaryl, preferably a substituted or unsubstituted (C6-C25) aryl, or substituted or unsubstituted (3-25 membered) heteroaryl, more preferably unsubstituted (C6-C20) aryl or substituted or unsubstituted (5-20 membered) heteroaryl. aryl, such as unsubstituted phenyl, unsubstituted biphenyl, unsubstituted naphthyl, unsubstituted dibenzothiophenyl, methyl substituted fluorenyl, methyl substituted benzofluorenyl, phenyl It may be a substituted carbazolyl, a phenyl substituted benzocarbazolyl, or an unsubstituted benzonaphthothiophenyl.

In Formulas 16 and 17, U is a single bond or a substituted or unsubstituted (C1-C6)alkylene, preferably a single bond.

In Formula 18, W is -NR-, -O-, -S- or -CR'R"-, preferably -NR-.

In Formula 18, R is a substituted or unsubstituted (C6-C30) aryl or a substituted or unsubstituted (3-30 membered) heteroaryl, preferably a substituted or unsubstituted (C6-C20) aryl. , More preferably unsubstituted (C6-C18) aryl, for example, it may be unsubstituted phenyl.

In Formula 18, R' and R" are each independently substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3-30 membered) Heteroaryl, preferably substituted or unsubstituted (C1-C20)alkyl, more preferably unsubstituted (C1-C15)alkyl, for example, may be unsubstituted methyl.

The compound represented by Chemical Formula 2 herein may be included not only in the electron transporting material of the electron transporting layer, but also in the electron buffering material of the electron buffering layer.

The compound represented by Formula 1 may be exemplified as the following compounds, but is not limited thereto.

The compound represented by Formula 2 may be exemplified as the following compounds, but is not limited thereto.

The compound of Formula 1 and the compound of Formula 2 of the present invention can be prepared using synthetic methods known to those skilled in the art, for example, bromination, Suzuki reaction, Buchwald-Hartwig reaction, Ullmann reaction, and the like.

The host used in the present invention may be a phosphorescent host compound or a fluorescent host compound. These host compounds are not particularly limited, and among known compounds, those having the LUMO energy value as described above may be selected and used. Specifically, the host compound may be a fluorescent host compound, for example, an anthracene compound represented by Chemical Formula 30 below.

[Formula 30]

In Formula 30,

Ar ₃₁ and Ar ₃₂ are each independently a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (5-30 membered) heteroaryl; Ar ₃₃ and Ar ₃₄ are each independently hydrogen, deuterium, halogen, cyano, nitro, hydroxy, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted, cyclic (5-30 membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted (C1-C30) alkylsilyl, substituted or unsubstituted (C6-C30)arylsilyl, substituted or unsubstituted (C6-C30)ar(C1-C30)alkylsilyl, or -NR ₄₁ R ₄₂ ; R ₄₁ and R ₄₂ are each independently hydrogen, a substituted or unsubstituted (C6-C30) aryl group, or a substituted or unsubstituted (5-30 membered) heteroaryl group; (C3-C30) may form a monocyclic or polycyclic alicyclic, aromatic or combination thereof ring, and the carbon atoms of the formed alicyclic, aromatic or combination thereof ring are nitrogen, oxygen and sulfur. may be replaced with one or more heteroatoms selected from; rr and ss are each independently an integer of 1 to 4, and when rr or ss is an integer of 2 or more, each of Ar ₃₃ or Ar ₃₄ may be the same as or different from each other.

The compound of Formula 30 may be specifically exemplified as the following compounds, but is not limited thereto.

The dopant used in the present invention may be a phosphorescent dopant compound or a fluorescent dopant compound. Specifically, the dopant compound may be a fluorescent dopant compound, for example, a condensed polycyclic amine derivative represented by Chemical Formula 40 below.

[Formula 40]

In Formula 40,

는 동일하거나 상이할 수 있다.Ar ₄₁ is a substituted or unsubstituted (C6-C50)aryl or styryl; L _a is a single bond, substituted or unsubstituted (C6-C30)arylene, or substituted or unsubstituted (3-30 membered)heteroarylene; Ar ₄₂ and Ar ₄₃ are each independently hydrogen, deuterium, halogen, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, or substituted or unsubstituted (3-30 membered) ) is heteroaryl; (C3-C30) may be combined with adjacent substituents to form a monocyclic or polycyclic alicyclic, aromatic or combination thereof ring, and the carbon atoms of the formed alicyclic, aromatic or combination thereof ring may be nitrogen, oxygen and sulfur; tt is 1 or 2, and when tt is 2, each

may be the same or different.

Preferred aryl groups in Ar ₄₁ include substituted or unsubstituted phenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted anthryl, substituted or unsubstituted pyrenyl, substituted or unsubstituted chrysenyl, substituted or unsubstituted benzofluorenyl groups, and spiro[fluorene-benzofluorene].

The compound of Formula 40 may be exemplified as the following compounds, but is not limited thereto.

The organic electroluminescent device of the present invention may further include a hole injection layer or a hole transport layer between the first electrode and the light emitting layer.

Hereinafter, a configuration and manufacturing method of an organic electroluminescent device will be described with reference to FIG. 1 .

1 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.

Referring to FIG. 1, an organic electroluminescent device 100 includes a substrate 101, a first electrode 110 formed on the substrate 101, an organic layer 120 formed on the first electrode 110, and the It faces the first electrode 110 and includes a second electrode 130 formed on the organic layer 120 .

The organic layer 120 includes a hole injection layer 122, a hole transport layer 123 formed on the hole injection layer 122, a light emitting layer 125 formed on the hole transport layer 123, and the light emitting layer 125. and an electron transfer zone 129 formed on the electron buffer layer 126, and the electron transfer zone 129 formed on the electron buffer layer 126 ( 127) and an electron injection layer 128 formed on the electron transport layer 127.

The light emitting layer 125 may be formed using a host compound and a dopant compound. The host compound and dopant compound are not particularly limited, and may be appropriately selected and used from known compounds. Examples of the host compound and the dopant compound are as described above. When the light emitting layer 125 includes the host and the dopant, the dopant may be doped in an amount of less than about 25% by weight, preferably less than 17% by weight, based on the total amount of the dopant and the host in the light emitting layer. When the light emitting layer 125 has two or more layers, each light emitting layer can emit different colors. For example, a white light emitting device can be manufactured by forming three light emitting layers 125 emitting blue, red, and green light, respectively. Also, if necessary, a yellow or orange light emitting layer may be included.

The electron buffer layer 126 may include an electron buffer material including the compound represented by Chemical Formula 1 or other electron buffer compounds. The thickness of the electron buffer layer 126 may be 1 nm or more, and is not particularly limited. Specifically, the thickness of the electron buffer layer 126 may be 2 to 200 nm. The electron buffer layer 126 may be formed on the light emitting layer 125 using various known methods such as a vacuum deposition method, a wet process, a laser transfer method, and the like. The electron buffer layer refers to a layer that controls the flow characteristics of charges. Accordingly, the electron buffer layer may trap electrons, block electrons, or lower an energy barrier between the electron transport band and the light emitting layer, for example.

The electron transfer zone 129 means a zone in which electrons are transferred from the second electrode to the light emitting layer. The electron transport zone 129 may include an electron transport compound, a reducing dopant, or a combination thereof. The electron transporting compound is a phenanthrene-based compound, an oxazole-based compound, an isoxazole-based compound, a triazole-based compound, an isothiazole-based compound, an oxadiazole-based compound, a thiadiazole-based compound, a perylene-based compound, an anthracene-based compound, an aluminum complex, And it may be at least one selected from the group consisting of gallium complexes. The reducing dopant may be at least one selected from the group consisting of alkali metals, alkali metal compounds, alkaline earth metals, rare earth metals, halides thereof, oxides thereof, and complexes thereof. Specific examples of the reducing dopant include lithium quinolate, sodium quinolate, cesium quinolate, potassium quinolate, LiF, NaCl, CsF, Li ₂ O, Bao, and BaF ₂ , but are not limited thereto. In addition, the electron transport zone 129 may include an electron transport layer 127, an electron injection layer 128, or both of them. Each of the electron transport layer 127 and the electron injection layer 128 may be composed of two or more layers. The electron transport layer 127 may include an electron transport material including a compound represented by Chemical Formula 2 of the present invention. In addition, the electron transport layer 127 may further include the aforementioned reducing dopant.

A known electron injection material may be used as a material used for the electron injection layer 128 . Examples include, but are not limited to, lithium quinolate, sodium quinolate, cesium quinolate, potassium quinolate, LiF, NaCl, CsF, Li ₂ O, BaO, and BaF ₂ .

The organic electroluminescent device of FIG. 1 is only one embodiment provided so that the contents of the present disclosure can be sufficiently conveyed to those skilled in the art, and the present invention is not limited to the embodiment, and may be embodied in other forms. For example, in the organic electroluminescent device of FIG. 1, an arbitrary component such as a hole injection layer other than the light emitting layer and the electron buffer layer may be omitted. Also, one optional component may be added. An example of one component that can be added is an impurity layer such as an n-doped layer and a p-doped layer. In addition, the organic electroluminescent device may be of a double-sided light emitting type by placing one light emitting layer on each side with the impurity layer interposed therebetween, and in this case, both light emitting layers may emit different colors. In addition, the first electrode is a transparent electrode and the second electrode is a reflective electrode to form a bottom emission type organic electroluminescent device, or the first electrode is a reflective electrode and the second electrode is a transparent electrode. It can also be set as a light emitting type organic electroluminescent element. In addition, a cathode, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and an anode may be stacked in this order on a substrate to form an inverted organic electroluminescent device.

2 schematically illustrates the relationship of energy gaps between layers of an organic electroluminescent device according to an embodiment of the present invention.

In FIG. 2, the hole transport layer 123, the light emitting layer 125, the electron buffer layer 126, and the electron transfer zone 129 are sequentially stacked, and the electrons (e) injected from the cathode pass through the electron transfer zone 129. Through the electron buffer layer 126, it is injected into the light emitting layer 125.

The LUMO energy value of the electron buffer layer 126 has an intermediate energy value between the host compound and the dopant compound of the light emitting layer 125 and the LUMO energy values of the electron transport layer 127 . Specifically, the LUMO energy value is in the relationship of the electron transport layer>electron buffer layer>light emitting layer. As shown in FIG. 2, although a LUMO energy difference of 0.5 eV or more occurs between the light emitting layer and the electron transport layer, electron transfer can be facilitated by inserting the corresponding electron buffer layer.

According to one aspect of the organic electroluminescent device of the present invention, the LUMO energy value (Ah) of the light emitting layer is greater than the LUMO energy value (Ad) of the dopant.

According to one aspect of the organic electroluminescent device of the present invention, the LUMO energy value (Ae) of the electron transport layer is greater than the LUMO energy value (Ab) of the electron buffer layer. Conversely, the LUMO energy value (Ae) of the electron transport layer may be smaller than the LUMO energy value (Ab) of the electron buffer layer.

According to one aspect of the organic electroluminescent device of the present invention, the LUMO energy value of the light emitting layer (Ah), the LUMO energy value of the electron buffer layer (Ab) and the LUMO energy value of the electron transport layer (Ae) are expressed by the following formulas (1) and ( 2) is satisfied.

|Ae - Ab| ≤ 0.3 eV (1)

|Ab - Ah| ≤ 0.4 eV (2)

For proper efficiency and long life, the following formula (3) is preferably satisfied.

Ae ≤ Ab + 0.2 eV (3)

For high efficiency, the following formula (4) is preferably satisfied.

Ab ≤ Ae + 0.2 eV (4)

Electron injection characteristics can be adjusted according to the combination of the electron buffer layer and the electron transport layer, and high efficiency and long lifespan characteristics can be adjusted according to the LUMO energy value along with the physical properties of the electron buffer layer. For example, when the LUMO energy values of the light emitting layer, the electron buffer layer, and the electron transport layer form a cascade as shown in FIG. 2, high efficiency is possible due to fast electron injection characteristics (in the case of Equation (4)). Conversely, when the LUMO energy value of the electron buffer layer is lower than that of the light emitting layer and the electron transport layer, there is an advantage in longevity by mitigating the electron current (in the case of Equation (3) above). In particular, high efficiency and long lifespan can be satisfied at the same time by using the compound combinations represented by Chemical Formulas 1 and 2 of the present invention.

The compound represented by Formula 2 used as the electron transport layer includes a phenanthroxazole-based compound and a phenanthrothiazole-based compound, which are highly electronegative and have an electron-rich group, as well as phenanthrene, oxazole, or phenane. As a structure in which groups such as threne and thiazole are fused, it has a rigid property and facilitates intermolecular transition. In addition, when such intermolecular stacking is strengthened, it is easy to implement horizontal molecular orientation, and through this, fast electron current characteristics can be implemented. Here, if triazine and pyrimidine derivatives are used as materials for the electron buffer layer in a limited structure, the stacking effect between molecules with the electron transport layer is maintained and at the same time, the driving voltage is relatively low through the improvement of the interface characteristics, and the current efficiency and power efficiency are improved. It is possible to provide an organic electroluminescent device capable of implementing high-purity colors while having excellent luminous efficiency.

The result of the relationship between the LUMO energy value (Ae) of the electron transport layer, the LUMO energy value (Ab) of the electron buffer layer and the LUMO energy value (Ah) of the light emitting layer is to explain the tendency of an alternative device according to the overall LUMO energy group It is intended for this purpose, and different results from the above results may appear depending on the inherent properties of a specific derivative and the stability of the material.

The electron buffer layer may be included in an organic light emitting device that emits all colors such as blue, red, and green. Preferably, it may be included in an organic electroluminescent device that emits blue light (ie, a main peak wavelength of 430 to 470 nm, preferably 450 nm).

In addition, a display device, for example, a display device for a smartphone, tablet, laptop, PC, TV, or vehicle, or a lighting device, for example, an outdoor or indoor lighting device, is manufactured using the organic electroluminescent device of the present disclosure. It is possible.

Hereinafter, for a detailed understanding of the present invention, representative compounds of the present invention will be described, and the method for preparing the compound according to the present invention and the emission characteristics of the organic electroluminescent device of the present invention will be described.

[ Example 1] Preparation of compound C-24

1) Preparation of compound 1-1

In a reaction vessel, compound A (CAS: 1044146-16-8, 36 g, 124 mmol), 4-chloro-2-formylbenzeneboronic acid (25.2 g, 136 mmol), tetrakis (triphenylphosphine) palladium (5.7 g, 5.0 mmol), sodium carbonate (33 g, 150 mmol), 600 mL of toluene, 150 mL of ethanol and 150 mL of distilled water were added, followed by stirring at 140°C for 3 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. The obtained compound 1-1 was used in the next reaction without further purification.

2) Preparation of compound 1-2

Compound 1-1 (45.6 g, 130 mmol), (methoxymethyl)triphenylphosphonium chloride (74.3 g, 217 mmol) and 1500 mL of tetrahydrofuran were added to a reaction vessel, and the reaction mixture was stirred for 5 minutes and potassium t -Butoxide (1 M in THF, 220 mL) was slowly added dropwise under 0°C condition. The temperature was slowly raised and stirred at room temperature for 3 hours. Distilled water was added to the reaction solution to terminate the reaction, and extraction was performed with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Thereafter, the product was purified by column chromatography to obtain compound 1-2 (48 g, yield 97%).

3) Preparation of compound 1-3

Compound 1-2 (44.8 g, 119 mmol), Eaton's reagent (4.5 mL) and 600 mL of chlorobenzene were added to a reaction vessel and refluxed for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with methylene chloride (MC). After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the compound 1-3 (36.3 g, yield 89%) was obtained by purification by column chromatography.

4) Preparation of compound C-24

In a reaction vessel, compound 1-3 (8 g, 23 mmol), compound B (CAS: 1060735-14-9, 9.5 g, 23 mmol), tris (dibenzylidineacetone) dipalladium (1 g, 1.16 mmol), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (0.95 g, 2.31 mmol), sodium t-butoxide (4.5 g, 46.3 mmol) and o-xylene 150 mL After addition, it was stirred at 170 °C for 3 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography to obtain compound C-24 (8.7 g, yield 68%).

[ Example 2] Preparation of compound C-1

1) Preparation of compound 2-1

In a reaction vessel, compound C (10 g, 29 mmol), bis (pinacolato) diborane (8.8 g, 34.8 mmol), tris (dibenzylidineacetone) dipalladium (1.3 g, 1.45 mmol), 2-dicyclo After adding hexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (1.2 g, 2.9 mmol), potassium acetate (8.5 g, 87 mmol) and 150 mL of 1,4-dioxane, Stirred at 140° C. for 3 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 2-1 (10.4 g, yield 82%).

2) Preparation of Compound C-1

In a reaction vessel, compound 2-1 (10 g, 23.8 mmol), 2-chloro-4,6-diphenyltriazine (CAS: 3842-55-5, 6.4 g, 23.8 mmol), tris (dibenzylidineacetone) dipalladium (1 g, 1.16 mmol), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (1 g, 2.31 mmol), sodium t-butoxide (4.5 g, 46.3 mmol) and 150 mL of o-xylene were added, and the mixture was stirred at 170° C. for 3 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography to obtain compound C-1 (8.2 g, yield 55%).

[ Example 3] Preparation of compound C-17

In a reaction vessel, compound C (8 g, 23.1 mmol), compound D (CAS: 1448296-00-1, 7.7 g, 23.1 mmol), tetrakis (triphenylphosphine) palladium (1.4 g, 1.19 mmol), potassium carbonate (8.2 g, 60 mmol), 90 mL of toluene, 30 mL of ethanol and 30 mL of distilled water were added, and the mixture was stirred at 140°C for 3 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. The obtained compound was purified by column chromatography to obtain compound C-17 (8.7 g, yield 77%).

[ Example 4] Preparation of compound C-39

1) Preparation of Compound 3-1

Compound E (CAS: 913835-76-4, 40 g, 212.7 mmol), benzaldehyde (27 g, 255.29 mmol), sodium cyanide (10.4 g, 212.7 mmol) and N, N-dimethylformamide ( After adding 1000 mL of DMF), the mixture was stirred at 100° C. for 3 hours. The reaction solution cooled to room temperature was extracted with ethyl acetate. The obtained compound 3-1 was used in the next reaction without further purification.

2) Preparation of compound 3-2

Compound 3-1 (35 g, 128 mmol), 4-chloro-2-formylbenzeneboronic acid (26 g, 141 mmol), tetrakis (triphenylphosphine) palladium (6 g, 5.1 mmol), After adding sodium carbonate (34 g, 320 mmol), toluene 600 mL, ethanol 150 mL and distilled water 150 mL, the mixture was stirred at 140° C. for 3 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. The obtained compound 3-2 was used in the next reaction without further purification.

3) Preparation of compound 3-3

Compound 3-2 (19 g, 56.9 mmol), (methoxymethyl)triphenylphosphonium chloride (29.3 g, 85.4 mmol) and 500 mL of tetrahydrofuran were added to a reaction vessel, and the reaction mixture was stirred for 5 minutes and potassium t -Butoxide (1 M in THF, 85 mL) was slowly added dropwise under 0°C condition. The temperature was slowly raised and stirred at room temperature for 3 hours. Distilled water was added to the reaction solution to terminate the reaction, and extraction was performed with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 3-3 (16.4 g, yield 80%).

4) Preparation of compounds 3-4

Compound 3-3 (14.4 g, 39.8 mmol), Eaton's reagent (1.4 mL) and 200 mL of chlorobenzene were added to a reaction vessel and refluxed for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with methylene chloride (MC). After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 3-4 (11.1 g, yield 79%).

5) Preparation of Compound C-39

In a reaction vessel, compound 3-4 (4 g, 12.1 mmol), compound B (CAS: 1060735-14-9, 4.9 g, 12.1 mmol), tris (dibenzylidineacetone) dipalladium (0.5 g, 0.61 mmol), 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (0.5 g, 1.21 mmol), sodium t-butoxide (2.33 g, 24.3 mmol) and o-xylene 100 mL After addition, it was stirred at 170 °C for 3 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography to obtain compound C-39 (8.7 g, yield 47%).

[ Example 5] Preparation of compound C-49

1) Preparation of Compound 2-1

Compound 2-1 was prepared in the same manner as described in Example 2.

2) Preparation of compound C-49

In a reaction vessel, compound 2-1 (4.5 g, 10 mmol), 2-chloro-4,6-diphenylpyrimidine (CAS: 2915-16-4, 2.7 g, 10 mmol), tetrakis (triphenylphosphine) ) After adding palladium (0.47 g, 0.4 mmol), potassium carbonate (3.6 g, 26 mmol), 50 mL of toluene, 13 mL of ethanol and 13 mL of distilled water, the mixture was stirred at 120° C. for 4 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography to obtain compound C-49 (4.5 g, yield 73%).

[ Example 6] Preparation of compound C-75

1) Preparation of compound 4-1

Compound F (7.2 g, 21.8 mmol), bis(pinacolato)diborane (6.6 g, 26.2 mmol), tris(dibenzylidineacetone)dipalladium (1.0 g, 1.1 mmol), 2-dicyclo After adding hexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (0.89 g, 2.2 mmol), potassium acetate (6.4 g, 65 mmol) and 150 mL of 1,4-dioxane, Stirred at 140° C. for 3 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 4-1 (5.2 g, yield 57%).

2) Preparation of compound C-75

In a reaction vessel, compound 4-1 (5.2 g, 12.3 mmol), 2-chloro-4,6-diphenylpyrimidine (CAS: 2915-16-4, 3.3 g, 12.3 mmol), tetrakis (triphenylphosphine) ) After adding palladium (0.71 g, 0.62 mmol), potassium carbonate (4.2 g, 30 mmol), toluene 60 mL, ethanol 20 mL and distilled water 20 mL, the mixture was stirred at 120° C. for 4 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography and recrystallization to obtain compound C-75 (5.3 g, yield 82%).

[ Example 7] Preparation of compound C-140

1) Preparation of Compound G

Compound G is the same as the manufacturing process of Compound 3-2 described in Example 4, except that 5-chloro-2-formylboronic acid was used instead of 4-chloro-2-formylbenzeneboronic acid in the manufacturing process of Compound 3-2. prepared in this way.

2) Preparation of compound 5-1

In a reaction vessel, compound G (15 g, 45.5 mmol), bis(pinacolato)diborane (13.9 g, 54.6 mmol), tris(dibenzylidineacetone)dipalladium (1.6 g, 1.8 mmol), 2-dicyclo After adding hexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (0.9 g, 3.64 mmol), potassium acetate (13 g, 136 mmol) and 350 mL of 1,4-dioxane, Stirred at 140° C. for 3 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 5-1 (20 g, yield 99%).

3) Preparation of compound C-140

In a reaction vessel, compound 5-1 (10 g, 22.7 mmol), 2-chloro-4,6-diphenylpyrimidine (CAS: 2915-16-4, 5.5 g, 20.6 mmol), tetrakis (triphenylphosphine) ) After adding palladium (1.2 g, 1.0 mmol), potassium carbonate (7.1 g, 56 mmol), toluene 90 mL, ethanol 30 mL and distilled water 30 mL, the mixture was stirred at 120° C. for 4 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography and recrystallization to obtain compound C-140 (5.5 g, yield 51%).

[ Example 8] Preparation of compound C-100

In a reaction vessel, compound 5-1 (10 g, 23.7 mmol), 2-chloro-4,6-diphenyltriazine (CAS: 3842-55-5, 5.8 g, 21.6 mmol), tetrakis (triphenylphosphine) ) After adding palladium (1.2 g, 1.0 mmol), potassium carbonate (7.5 g, 59 mmol), toluene 90 mL, ethanol 30 mL and distilled water 30 mL, the mixture was stirred at 120° C. for 4 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography and recrystallization to obtain compound C-100 (5.7 g, yield 50%).

[ Example 9] Preparation of compound C-45

1) Preparation of compound 9-1

In a reaction vessel, the compound 7-bromo-2-phenyl-benzoxazole (37 g, 135 mmol), 4-chloro-2-formylbenzeneboronic acid (25 g, 135 mmol), tetrakis (triphenylphosphine) After adding palladium (7.8 g, 6.7 mmol), sodium carbonate (35 g, 338 mmol), toluene 680 mL, ethanol 170 mL and distilled water 170 mL, the mixture was stirred at 130° C. for 3 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. Then, the product was purified by column chromatography to obtain compound 9-1 (26 g, yield 60%).

2) Preparation of Compound 9-2

Compound 9-1 (26 g, 80.2 mmol), (methoxymethyl)triphenylphosphonium chloride (41 g, 120 mmol) and 800 mL of tetrahydrofuran were added to a reaction vessel, and the reaction mixture was stirred for 5 minutes and potassium t -Butoxide (1 M in THF, 120 mL) was slowly added dropwise under 0°C condition. The temperature was slowly raised and stirred at room temperature for 3 hours. Distilled water was added to the reaction solution to terminate the reaction, and extraction was performed with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 9-2 (25 g, yield 87%).

3) Preparation of Compound 9-3

Compound 9-2 (25 g, 70.2 mmol), Eaton's reagent (3 mL) and 350 mL of chlorobenzene were added to a reaction vessel and refluxed for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with methylene chloride (MC). After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 9-3 (13 g, yield 56%).

4) Preparation of compound 9-4

In a reaction vessel, compound 9-3 (13 g, 39 mmol), bis(pinacolato)diborane (12 g, 47 mmol), tris(dibenzylidineacetone)dipalladium (1.8 g, 1.9 mmol), 2- Dicyclohexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (1.6 g, 3.9 mmol), potassium acetate (11 g, 118 mmol) and 330 mL of 1,4-dioxane were added. After that, the mixture was stirred at 130° C. for 4 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Thereafter, the product was purified by column chromatography to obtain compound 9-4 (13 g, yield 81%).

5) Preparation of Compound C-45

In a reaction vessel, compound 9-4 (13 g, 31 mmol), 2-chloro-4,6-diphenyltriazine (8 g, 30 mmol), tetrakis (triphenylphosphine) palladium (1.7 g, 1.5 mmol) ), potassium carbonate (10 g, 75 mmol), 140 mL of toluene, 35 mL of ethanol, and 35 mL of distilled water were added, followed by stirring at 130°C for 4 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. Thereafter, the product was purified by column chromatography to obtain compound C-45 (7.7 g, yield 49%).

[ Example 10] Preparation of compound C-141

In a reaction vessel, compound 9-4 (3 g, 7.1 mmol), 2-(3-bromophenyl)-4,6-diphenyl-1,3,5-triazine (CAS: 864377-31-1, 3.04 g, 7.8 mmol), tetrakis(triphenylphosphine)palladium (0.41 g, 0.36 mmol), sodium carbonate (1.9 g, 17.8 mmol), 24 mL of toluene, 6 mL of ethanol and 6 mL of distilled water were added, followed by 120 ° C. was stirred for 4 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography and recrystallization to obtain compound C-141 (2.3 g, yield 54%).

[ Example 11] Preparation of compound C-142

Compound 9-4 (3.48 g, 8.3 mmol), 2-([1,1'-biphenyl]-4-yl)-4-chloro-6-phenyl-1,3,5-triazine ( CAS: 1472062-94-4, 3.53 g, 9.1 mmol), tetrakis(triphenylphosphine)palladium (0.48 g, 0.41 mmol), sodium carbonate (2.2 g, 20.7 mmol), 28 mL of toluene, 7 mL of ethanol and distilled water After adding 7 mL, it was stirred at 120° C. for 5 hours. After the reaction was completed, the mixture was added dropwise to methanol, and the resulting solid was filtered. The resulting solid was purified by column chromatography and recrystallization to obtain compound C-142 (3.7 g, yield 74%).

[ Example 12] Preparation of compound C-101

1) Preparation of Compound 10-1

Compound A (20 g, 76.0 mmol), benzaldehyde (8.1 g, 76.0 mmol), p-toluenesulfonic acid (1.5 g, 7.6 mmol), and 380 mL of ethanol were added to the reaction vessel, followed by refluxing and stirring for 24 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. Then, the product was purified by column chromatography to obtain compound 10-1 (20 g, yield 75%).

2) Preparation of Compound 10-2

Compound 10-1 (20 g, 57.3 mmol), 4-chloro-2-formylbenzeneboronic acid (10.6 g, 57.3 mmol), tetrakis (triphenylphosphine) palladium (2.0 g, 1.7 mmol), After adding sodium carbonate (15.2 g, 143.3 mmol), toluene 300 mL, ethanol 100 mL and distilled water 100 mL, the mixture was stirred at 120° C. for 3 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. Then, the product was purified by column chromatography to obtain compound 10-2 (16.5 g, yield 70%).

3) Preparation of Compound 10-3

Compound 10-2 (16.5 g, 40.4 mmol), (methoxymethyl)triphenyl phosphonium chloride (21 g, 61 mmol) and 400 mL of tetrahydrofuran were added to a reaction vessel, and the reaction mixture was stirred for 5 minutes, and potassium t- Butoxide (1 M in THF, 60 mL) was slowly added dropwise under 0°C condition. The temperature was slowly raised and stirred at room temperature for 3 hours. Distilled water was added to the reaction solution to terminate the reaction, and extraction was performed with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, the product was purified by column chromatography to obtain compound 10-3 (12 g, yield 68%).

4) Preparation of Compound 10-4

Compound 10-3 (12 g, 27.5 mmol), Eaton's reagent (1.2 mL) and 140 mL of chlorobenzene were added to a reaction vessel and refluxed for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and extracted with methylene chloride (MC). After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 10-4 (8 g, yield 72%).

5) Preparation of Compound 10-5

Compound 10-4 (8 g, 19.8 mmol), bis(pinacolato)diborane (6 g, 23.7 mmol), tris(dibenzylidineacetone)dipalladium (0.7 g, 0.8 mmol), 2- Dicyclohexylphosphino-2',6'-dimethoxybiphenyl (s-phos) (0.7 g, 1.6 mmol), potassium acetate (5.8 g, 59.4 mmol) and 100 mL of 1,4-dioxane were added. After stirring under reflux for 4 hours at 130 ℃. After the reaction was completed, the mixture was cooled to room temperature and extracted with ethyl acetate. After drying the extracted organic layer with magnesium sulfate, the solvent was removed using a rotary evaporator. Then, it was purified by column chromatography to obtain compound 10-5 (7 g, yield 71%).

6) Preparation of compound C-101

In a reaction vessel, compound 10-5 (5 g, 10.1 mmol), 2-chloro-4,6-diphenyltriazine (2.7 g, 30 mmol), tetrakis (triphenylphosphine) palladium (0.4 g, 0.3 mmol) ), sodium carbonate (3.5 g, 25.3 mmol), 50 mL of toluene, 12 mL of ethanol, and 12 mL of distilled water were added, followed by stirring at 120 °C for 4 hours. After the reaction, the precipitated solid was washed with distilled water and methanol. Thereafter, the product was purified by column chromatography to obtain compound C-101 (4.1 g, yield 67%).

The physical properties of the synthesized compound are summarized in Table 1 below.

[Table 1]

[ comparative example 1] blue light emission organic not according to the present invention electric field Manufacture of Light-Emitting Devices

OLED devices not according to the present invention were prepared. First, a transparent electrode ITO thin film (10Ω/□) on a glass substrate for OLED (manufactured by Geomatec Co.) was washed with ultrasonic waves using acetone and isopropyl alcohol sequentially, and then stored in isopropanol before use. Next, after mounting the ITO substrate on the substrate holder of the vacuum deposition equipment, N ⁴ ,N ^{4 '} -diphenyl-N ⁴ ,N ^{4 '} -bis(9-phenyl-9H-carbazole- 3-day) -[1,1'-biphenyl] -4,4'-diamine (compound HI-1) was added, and the vacuum in the chamber was evacuated until it reached 10 ^-7 torr, and then a current was applied to the cell. After applying and evaporating, a first hole injection layer having a thickness of 60 nm was deposited on the ITO substrate. Subsequently, 1,4,5,8,9,12-hexaazatriphenylene-hexacarbonitrile (compound HI-2) was put into another cell in the vacuum deposition equipment, and an electric current was applied to the cell to evaporate it, thereby forming a first hole A second hole injection layer having a thickness of 5 nm was deposited on the injection layer. Then N-([1,1'-biphenyl]-4-yl)-9,9-dimethyl-N-(4-(9-phenyl-9H-carbazole-3- 1) Phenyl) -9H-fluoren-2-amine (compound HT-1) was put thereinto, and an electric current was applied to the cell to evaporate it, thereby depositing a first hole transport layer having a thickness of 20 nm on the second hole injection layer. Then, in another cell in the vacuum deposition equipment, 9-(naphthalen-2-yl)-3-(4-(9-phenyl-9H-carbazol-3-yl)phenyl)-9H-carbazole (compound HT-2 ) was put, and a second hole transport layer having a thickness of 5 nm was deposited on the first hole transport layer by evaporating by applying a current to the cell. After forming the hole injection layer and the hole transport layer, the light emitting layer was deposited thereon as follows. After putting compound H-82 as a host in one cell in the vacuum evaporation equipment and compound D-38 as a dopant in another cell, respectively, the two materials were evaporated at different rates to obtain a dopant for the total amount of host and dopant. A light emitting layer having a thickness of 20 nm was deposited on the hole transport layer by doping it in an amount of 2% by weight. Subsequently, BCP (compound ETL-1) was placed in one cell as an electron transport material on the light emitting layer and evaporated to deposit an electron transport layer having a thickness of 35 nm. Subsequently, after depositing lithium quinolate (compound EIL-1) to a thickness of 2 nm as an electron injection layer, an Al cathode was deposited to a thickness of 80 nm using another vacuum deposition equipment to manufacture an OLED device. Each compound for each material was used after vacuum sublimation purification under 10 ^-6 torr.

[Table 2] shows the driving voltage, luminous efficiency, CIE color coordinates, and lifetime of the organic EL device manufactured as described above based on luminance of 1,000 nits, and life time until the luminance drops from 100% to 50%. In addition, the current efficiency according to the luminance of the organic electroluminescent device prepared in Comparative Example 1 is shown as a graph in FIG. 3 .

[ comparative example 2] blue light emission organic not according to the present invention electric field Manufacture of Light-Emitting Devices

An OLED device was prepared and evaluated in the same manner as in Comparative Example 1, except that Alq ₃ (compound ETL-2) was used as an electron transfer material. The evaluation results of the organic electroluminescent device of Comparative Example 2 are shown in [Table 2].

[ comparative example 3 and 4] blue emission organic not according to the present invention electric field Manufacture of Light-Emitting Devices

Instead of forming the electron transport layer with a thickness of 35 nm, 5 nm of BCP (compound ETL-1) was deposited as an electron buffer layer, and then 30 nm of Alq ₃ (compound ETL-2) was deposited as an electron transport layer (Comparative Example 3) Comparative Example 1 and Comparative Example 1, except for depositing 5 nm of compound B-21 as an electron buffer layer and then depositing 30 nm of compound ETL-3:Liq at a weight ratio of 50:50 as an electron transport layer (Comparative Example 4). OLED devices were prepared and evaluated in the same manner. The evaluation results of the organic electroluminescent devices of Comparative Examples 3 and 4 are shown in Table 2 below.

[device Example 1 to 5] blue light emitting organic material according to the present invention electric field Manufacture of Light-Emitting Devices

In Device Examples 1 to 5, Comparative Example 1 except for depositing 5 nm of the compound of [Table 2] as an electron buffer layer and then depositing 30 nm of compound C-45:Liq at a weight ratio of 50:50 as an electron transport layer. An OLED device was prepared and evaluated in the same manner as described above. The evaluation results of the organic electroluminescent devices of each device example 1 to 5 are shown in [Table 2] below. In addition, the current efficiency according to the luminance of the organic electroluminescent device manufactured in Device Example 1 is graphed in FIG. 3 .

[Table 2]

[ comparative example 5 and 6] blue light emission organic not according to the present invention electric field Manufacture of Light-Emitting Devices

An OLED device was prepared and evaluated in the same manner as in Comparative Example 1, except that the host was used as compound H-15 and used as an electron transfer material as shown in Table 3 below. The evaluation results of the organic electroluminescent devices of Comparative Examples 5 and 6 (life time is the time until the luminance drops from 100% to 90%) are shown in [Table 3] below.

[ comparative example 7] Blue light emission organic not according to the present invention electric field Manufacture of Light-Emitting Devices

Comparison, except that instead of forming the electron transport layer at 35 nm, 5 nm of BCP (compound ETL-1) was deposited as an electron buffer layer and then 30 nm of Alq ₃ (compound ETL-2) was deposited as the electron transport layer. OLED devices were prepared and evaluated in the same manner as in Examples 5 and 6. The evaluation results of the organic electroluminescent device of Comparative Example 7 are shown in Table 3 below.

[device Example 6 to 9] blue light emission organic according to the present invention electric field Manufacture of Light-Emitting Devices

In Device Examples 6 to 9, after depositing 5 nm of the compound of [Table 3] as an electron buffer layer, Comparative Example 5 except for depositing 30 nm of compound C-142:Liq at a weight ratio of 50:50 as an electron transport layer. and 6, an OLED device was prepared and evaluated in the same manner. The evaluation results of the organic electroluminescent devices of each device example 6 to 9 are shown in [Table 3].

[Table 3]

From [Table 2] and [Table 3], Device Examples 1 to 5 and Device Examples 6 to 9 were compared to Comparative Examples 1 to 4 and Comparative Examples, respectively, through an appropriate combination of the electron buffer layer and the electron transport layer of the present invention. When compared with 5 to 7, it showed low driving voltage, high efficiency and long life characteristics. In particular, when comparing Device Example 2 to Comparative Example 4, it showed a characteristic increased by 30% or more in terms of lifetime. This is considered to be easy for flexible displays, lighting and automotive displays requiring long lifespan.

[Table 4] Compounds used in Comparative Examples and Device Examples

100: organic light emitting element 101: substrate
110: first electrode 120: organic layer
122: hole injection layer 123: hole transport layer
125: light emitting layer 126: electron buffer layer
127: electron transport layer 128: electron injection layer
129 electron transport band 130 second electrode

Claims (10)

a first electrode; a second electrode facing the first electrode; a light emitting layer between the first electrode and the second electrode; And an electron transport layer and an electron buffer layer between the light emitting layer and the second electrode,
The electron buffer layer includes a compound represented by Formula 1 below,
The electron transport layer is an organic electroluminescent device comprising a compound represented by Formula 2 below.
[Formula 1]

[Formula 2]

In Formulas 1 and 2,
N ₁ and N ₂ are each independently N or CR ₁₁ provided that at least one of N ₁ and N ₂ is N;
X ₁ to X ₃ are each independently N or CR ₁₂ ;
Y ₁ is N or CR ₁₃ ;
R ₁₁ to R ₁₃ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C50)aryl, substituted or unsubstituted (3- 50 member) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tri(C1-C30) alkylsilyl, substituted or unsubstituted Di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri(C6-C30)arylsilyl, substituted Or unsubstituted mono- or di- (C1-C30) alkylamino, substituted or unsubstituted mono- or di- (C6-C30) arylamino, or substituted or unsubstituted (C1-C30) alkyl (C6- C30) arylamino; It may be linked to an adjacent substituent to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic or combination thereof ring, and the carbon of the formed alicyclic, aromatic or combination thereof ring atoms may be replaced by one or more heteroatoms selected from nitrogen, oxygen and sulfur;
A ₁ is -N=, -NR ₇ -, -O- or -S-;
B ₁ is -N=, -NR ₈ -, -O-, or -S-, wherein, when A ₁ is -N=, B ₁ is -NR ₈ -, -O-, or -S-, and A ₁ is - B ₁ when NR ₇ - is -N=, -O- or -S-;
R ₁ is a substituted or unsubstituted (C6-C30)aryl or a substituted or unsubstituted (3-30 membered) heteroaryl;
R ₂ to R ₄ , R ₇ and R ₈ are each independently hydrogen, deuterium, halogen, cyano, substituted or unsubstituted (C1-C30)alkyl, substituted or unsubstituted (C6-C30)aryl, substituted or unsubstituted Unsubstituted (3-30 membered) heteroaryl, substituted or unsubstituted (C3-C30) cycloalkyl, substituted or unsubstituted (C1-C30) alkoxy, substituted or unsubstituted tri(C1-C30) alkylsilyl , substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, substituted or unsubstituted tri(C6- C30) arylsilyl, substituted or unsubstituted mono- or di- (C1-C30) alkylamino, substituted or unsubstituted mono- or di- (C6-C30) arylamino, or substituted or unsubstituted (C1- It may be C30)alkyl(C6-C30)arylamino, or may be linked to an adjacent substituent to form a substituted or unsubstituted (C3-C30) monocyclic or polycyclic alicyclic, aromatic, or a combination thereof ring. A carbon atom of an alicyclic, aromatic or combination ring may be replaced with one or more heteroatoms selected from nitrogen, oxygen and sulfur;
a is 1, b and c are each independently 1 or 2, d is an integer from 1 to 4;
The heteroaryl (ene) includes one or more heteroatoms selected from B, N, O, S, Si and P. According to claim 1, wherein Formula 1 is represented by Formula 3, the organic electroluminescent device.
[Formula 3]

In Formula 3,
Ar ₁ and Ar ₂ are as defined for R ₁₂ ;
Y ₁ is as defined in claim 1;
L is a single bond, substituted or unsubstituted (C6-C50) arylene, or substituted or unsubstituted (5-50 membered) heteroarylene;
Ar is a substituted or unsubstituted (C6-C50) aryl or a substituted or unsubstituted (5-50 membered) heteroaryl. According to claim 2, wherein the formula 3 is represented by any one of formulas 4 to 8, the organic electroluminescent device.
[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

In Formulas 4 to 8,
Ar ₁ , Ar ₂ , Y ₁ and L are as defined in claim 2;
Ar ₃ to Ar ₉ and Ar ₁₃ to Ar ₁₉ each independently have the same definition as Ar ₁ ;
X is CRaRb, NRc, O or S, wherein Ra, Rb and Rc are each independently the same as the definition of Ar ₁ ;
K is CRd or N, where Rd is as defined for Ar ₁ ;
M is O or S;
e, f, h, i and p are each independently an integer of 1 to 4, g and q are each independently an integer of 1 to 3, and n, o, r and s are each independently 1 or 2. The organic electroluminescent device according to claim 3, wherein Formula 4 is represented by any one of Formulas 10 to 14 below.
[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

In Formulas 10 to 14,
Ar ₁ , Ar ₂ , Y ₁ , L and X are as defined in claim 3;
R ₂₁ to R ₃₅ each independently have the same definition as Ar ₁ ;
Z is as defined for X;
L ₁ and L ₂ are each independently the same as the definition of L;
aa, dd, ee, gg, hh, jj, kk, and pp are each independently an integer from 1 to 4, bb, cc, ii, nn, and qq are each independently an integer from 1 to 3, and ff is 1 or 2. The organic electroluminescent device according to claim 1, wherein the compound represented by Formula 1 is selected from the following compounds.

The organic electroluminescent device according to claim 1, wherein the compound represented by Formula 2 is selected from the following compounds.

The method of claim 1, wherein the light emitting layer includes a host compound and a dopant compound, the lowest unoccupied molecular orbital (LUMO) energy value of the electron buffer layer is greater than the LUMO energy value of the host compound, and the LUMO energy of the electron transport layer A value greater than or less than the LUMO energy value of the electron buffer layer, the organic electroluminescent device. The method of claim 1, wherein the LUMO energy value (Ah) of the light emitting layer, the LUMO energy value (Ab) of the electron buffer layer and the LUMO energy value (Ae) of the electron transport layer are expressed by the following equations (1) and (2) Which satisfies, an organic electroluminescent device.
|Ae - Ab| ≤ 0.3 eV (1)
|Ab-Ah| ≤ 0.4 eV (2) The method of claim 1, wherein the LUMO energy value (Ab) of the electron buffer layer and the LUMO energy value (Ae) of the electron transport layer satisfy Equation (3) or Equation (4) below, or both of them. That is, an organic electroluminescent device.
Ae ≤ Ab + 0.2eV (3)
Ab ≤ Ae + 0.2 eV (4) The organic electroluminescent device according to claim 1, wherein the electron transport layer further comprises a reducing dopant.

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